Sep 25 2009
With their semiconductive characteristics, layers made of small titanium oxide tubes have been raising interest for several years, for they can be used especially well in Biotechnology or Solar Cell technology. Now they can attain a quality, which was until recently missing: an electrical conductivity that resembles those of metals.
A team from University of Erlangen-Nürnberg and the University Turku in Finnland “borrows” the conductivity that carbon brings about and embeds it into the titanium compound. The tube structure remains virtually unaltered, explains Prof. Dr. Patrik Schmuko from the University of Erlangens chair for surface science and corrosion.
The process is called carbonisation. It creates a new material with semi-metallic properties, which is also much more firm than the original compound. High electrical conductivity as well as favourable electrochemical properties define its role as an interesting new material for electrodes. Particularly the operation in methanol fuel cells seems to be appealing, for their performance could be improved drastically.
Prof. Schmuki estimates the improvement of the catalyst’s activity for methanol-oxidation to be about 700 percent. “Titanium Dioxide Nano-tubes have been in discussion as an alternative to carbon as substrate material for a while now. But our new conductive oxy-carbide performs much better even.